In Tokyo's downtown district of Ikebukuro, amidst many strange rumors and warnings of anonymous gangs and dangerous occupants, one urban legend stands out above the rest—the existence of a headless "Black Rider" who is said to be seen driving a jet-black motorcycle through the city streets. Mikado Ryuugamine has always longed for the excitement of the city life, and an invitation from a childhood friend convinces him to move to Tokyo. Witnessing the Black Rider on his first day in the city, his wishes already seem to have been granted. But as supernatural events begin to occur, ordinary citizens like himself, along with Ikebukuro's most colorful inhabitants, are mixed up in the commotion breaking out in their city.
Kida learns that he has been marooned by the Yellow Scarves. Celty confronts Mikado and reveals the truth about Kida and Sonohara. Meanwhile, Shizuo knocks on Shinra's door, heavily wounded by the gun shots. Shinra gives him medical treatment while Shizuo swears to kill Kida and the Yellow Scarves for shooting him. Sonohara then runs away, wanting to warn Kida. Kida returns to the Yellow Scarves hideout and learns that the Blue Squares have taken over Yellow Scarves from the inside. He then attempts to kill Horoda now that he has no affiliation to them. Kida is beaten up badly by the Yellow Scarves and puts up a fight until Horoda is about to shoot him, but one of Saika's children in Yellow Scarves knocks away the gun just in time. Sonohara bursts into the hideout, followed by Mikado and Celty on a motorcycle.Watch Now:Amazon
Half of the Blue Squares turned Yellow Scarves members counter attack Horoda as they reveal themselves as Kadota and 30 other of his friends. Kida is then taken to the hospital by Mikado and Anri while Celty chases Horoda who managed to escape the warehouse. While running away with the rest of his main gang, they encounter Shizuo who hurls a big sign post and chops the roof of their car. Celty then stops knowing that they encountered Shizuo but the Ikebukuro police then manage to eventually arrest Horoda and his gang. Kida is put into hospital as Anri confronts Izaya near the hospital, telling him her desire to kill him after he was the one actually behind all of the problems they encountered. Izaya manages to escape Anri, telling her that he isn't weak if he can manage to go up against Shizuo. While Izaya walks home he meets Simon but Simon immediately punches Izaya in the eye and they talk in Russian about what Izaya did. Back in the hospital, Kida wakes up to Saki standing in his room and they confess their love to each other. The next day, Kida and Saki leave Ikebukuro together with Kida giving a note to his school and Mikado and Anri stick together. That night, the Dollars is reborn as Mikado notices that Kida has joined the chat and he is happy that he can manage to stay in touch with his best friend. Kida and Saki are last seen leaving on a train somewhere in the country and Mikado and Anri on the top of their school building saying that Kida will come back.Watch Now:Amazon
Just as Shizou defeats Shuji, Celty takes the knife he drops and shows it to Shinra claiming that it could be Saika. Haruna Niekawa the daughter of Shuji comes to visit Anri to discuss about Nasujima, the teacher who harrases Anri. Shinra and Celty discussing about Saika, discover that Saika loves humans so much that it demonstrates her love via actions manipulating her host. They also find out multiple Saikas in the chat room as they find out that Saika slashes humans just as it leaves her "children" to manipulate multiple hosts. Celty decides to go for Shizou who went to fight Izaya who could be a target of Saika, not much later a multitude of hosts get around Shizou claiming they "love" his power. Shizou now liking his own power for the first time decides to fight back. While Nasujima is being chased by a possessed Haruna, Anri is attacked by multiple Saika-hosts. Haruna then is able to corner Nasujima, however Anri asks her to stop slashing people, just as Haruna attacks Anri, she is left unharmed as Anri reveals she is in fact, the wielder of the true Saika.Watch Now:Amazon
Mikado phones Namie proposing a deal, Namie attends with some followers around. Mikado claims he has Mika and demands the "truth" behind what she has done to Mika, she does (unknown to the viewer) while Kadota brings Mika to Celty at the roof of a building nearby Mikado and Namie. Mikado disguisted by the truth asks Namie to turn herself in, she thinking of Mikado's thoughts as nonsense orders her henchmen to move, however Mikado revealing himself as the leader of the Dollars sends massive-multiple email through his cell phone which is in fact sent towards the large mass of people of Ikebukuro who are in fact members of Dollars, ordered to only stare Namie and her workers. It is revealed that Mikado created the Dollars in hopes to create a rumor which would spread, however his plans were brought down when people calling himself Dollars were doing evil. In desperation Mikado left messages about Dollars being a group to do good, which in fact worked. Just as Namie and her followers are desperate, Celty with a high resolution over her existance caring little if she is seen as a monster, decides to attack the Yagiri workers defeating them, although revealing herself as "headless" causing panic among the people. Just as this happens Seiji in an enranged behaviour decides to attack Mikado knowing he knows where "Celty" is.
Confusion is starting to descend on the town of Ikebukuro. Izaya grins with an evil smile... everything is going according to plan. Unaware of Izaya's plan, Masaomi is remembering the past in an abandoned building. How he came back here. How a girl named Mikajima Saki still waits for him at the hospital. He remembers the words Izaya once said to him: "You can never run from your past."Watch Now:Amazon
Sonohara is being taken away by the Yellow Scarves gang but Mikado asks the Dollars to help her. Izaya sees this too and decides to observe from afar. She escapes with the help of various members of the Dollars (to which she is unaware), but is found again until Kida grabs her hand and secretly helps her escape from them. He then asks her what she wants from all this and accuses her of tricking him while sucking up to Mikado; disgusted by these accusations, Anri slaps him and walks away. Kida then regrets saying those things. Sonohara is once again found by the Yellow Scarves, then saved from them by Shizuo and is then taken to safety in Celty's house. Celty then lets Sonohara live with her for the time being. After an increasing amount of violent attacks by the Yellow Scarves, resulting in severe injuries, Mikado disbands the Dollars (much to the protests of the Dollar members). Meanwhile, Celty decides to bring Mikado to her house to convince him to stop the gang war, and also so that he can tell Sonohara the truth about himself. Kida calls Mikado repeatedly but he refuses to answer the phone calls. At the same time, some Yellow Scarves (Horoda and his gang) shoot Shizuo and falsely claim that Kida Masaomi had ordered them to do so.Watch Now:Amazon
Mikado runs away with Mika and shelters her into his apartment. However, in the following day, he is approached by Celty and Izaya, and after telling her secret to him, Celty convinces Mikado to help her find Mika. Unfortunately, Mikado is cornered by some Yagiri Pharmacy workers who question him on Mika's whereabouts. In order to save Mika, Mikado reveals to Izaya and Celty his secret.
As Izaya’s scheme exposes Chikage’s girlfriend to danger, Mikado attempts to stop the cruel reality caused by a runaway Dollars. Meanwhile, Akane returns home with Celty, but the conflict over Akane seems destined to converge…
Sonohara pokes Niekawa with Saika, and shows her a flashback of how she became its wielder. Sonohara's father was an antiquities dealer, and constantly beat up her and her family. Her mother then got possessed by Saika, killed her father, and committed suicide. Sonohara then grabs the cursed blade, and becomes its wielder. Meanwhile, Shizuo beats up Niekawa's "Saika children," flashing back to his past. Sonohara then assimilates Niekawa's Saika, and as a result takes control of all of the Saikas in Ikebukuro. Sonohara apologizes to Celty for attacking her back in Episode 5. Mikado later visits Sonohara at the hospital, and after realizing she has met the "unusual people," warns her to stay away from the non-normal. As a result of Niekawa's assimilation, Sonohara has gained her and all of the Saika's memories; she suspects that Izaya is up to something. Mikado is later shown contacting members of the Dollars, but it is unknown for what reason. The episode concludes, as Izaya's plot deepens further; he is revealed to be behind several events in the slasher arc. He has caused a split of the city's population into different "factions;" Saika/Sonohara's army, the Yellow Scarves, and the Dollars; and knows that they will fight amongst each other. Kida, not knowing Anri Sonohara's true nature, retakes his place as the leader of the Yellow Scarves. He suspects the Dollars to be responsible for Sonohara's injuries, and vows revenge.
Namie has flooded the chat room with messages calling out Mikado and demanding he take responsibility for the situation she claims he’s created. Meanwhile, Shooter and Shizuo race to Celty and a confrontation with Kasane and Seitaro.
Using a number of pseudonyms, Izaya has continued to cause an uproar from behind the scenes. One of these pseudonyms is a story that goes back 12 years ago, from the time he was a middle school student along with Shinra.
After losing contact with her brother Seiji, Namie Yagiri enlists Izaya's help to find him. While roaming through Ikebukuro, Seiji and Mika Harima stumble onto Shizuo and Celty and a heated pursuit begins after Celty figures that the head attached to Mika's body is actually hers.Watch Now:Amazon
Rumors spread about “Ikebukuro’s most dangerous man,” claiming things like, “He’s injured. He has a girlfriend. He has a child.” After her defeat by Shizuo, Varona has lost her sense of purpose. At Dennis’ suggestion, she…
Celty runs away from home after arguing with Shinra, and an exchange student asks people to write what they're looking for in a notebook she carries.Watch Now:Amazon
It is discovered that Harima Mika is actually alive, and that Celty's head is being held by Yagiri Pharmacy. Shinra had known about it, and kept the secret from Celty for the fear of losing her because of her head's will.
He was in love with Ruri Hijiribe. That was the reason why he became a stalker and loved her so intensely that he wanted to destroy her soul. All the suffering Ruri had gone through, and the reason for the killer, Hollywood, will be revealed.
Chikage approaches the Yellow Scarves with a choice, “Have your gang taken over, or have it destroyed.” While Masaomi decides how to respond to this, Anri learns more about Saika and must make a decision of her own.
Everyone involved with Ruri is becoming the target of the stalker. Shizuo and Masaomi find themselves caught up in the action and encounter a member of Blue Square in the midst of it. With Anri in imminent danger, Masaomi seeks out the truth.
Two killers in the Russian wilderness discuss the fugitives that have violated their unwritten law. After fleeing the company, Varona and Sloan act as hitmen in Japan. Dennis and Simon watch on as Egor, the “Philosophical Killing Machine” gives chase.
By one girl’s hand, the existence of the head is made known to the public. In response to the news, Mikado makes a phone call. Meanwhile, Haruna makes a proposal to Anri…
A journalist named Shuji Niekawa is beaten up by Shizuo six months ago while trying to research who is the strongest person in Ikebukuro. As he goes around interviewing Simon, Izaya and Celty, Niekawa narrates his feelings on his latest work and the regret of not able to bond with his distant daughter, Haruna. After heading back home from a long day of work, Niekawa is attacked by the slasher who stabs him with a kitchen knife. After he survives the attack with no memory of the incident and awakes in hospital, Niekawa is possessed by the slasher spirit and directed to look for Anri, who was heading back home in episode 14. As he attempts to attack, Kyohei and his gang knock Niekawa down and rescue Anri. However, Niekawa gets back up to attack a second time but is knocked down by Celty on her bike with Shizuo in tow. Upon seeing Shizuo, the demonic spirit in Niekawa professes its love for him. Shizuo is enraged on hearing the slasher's confession and rips out a car door to bludgeon Niekawa.
Izaya is overjoyed at Mikado’s behavior, which has greatly exceeded his expectations, and grows more excited at the future uproar he is ushering in. Masaomi and Chikage talk through things, while Saki and Anri break the ice.
The number of Saika possessed people continues to increase as they fill the area around Russia Sushi. Anri heads to visit Celty and the Blue Square prepare to confront Chikage, all while Izaya and Shizuo fight to the death.